Correct answer:
mi, tu
Both mi and tu are possessive adjectives. Possessive adjectives are used to indicate ownership or possession. They agree in both gender and number with the thing possessed, not the possessor. Since Carla's mother is taller than Valeria's mother, then we say that:
Carla: Entonces, mi madre mide más que tu madre (So, my mother is taller than your mother)
